1. Technical Field
This disclosure relates generally to heat exchanger systems and, more particularly, to manifold assembly for a heat exchanger system.
2. Background Information
Heat exchanger systems, such as parallel flow heat exchanger systems (“parallel flow system”), are utilized in both condenser and evaporator applications for multiple products and system designs and configurations. Typically, a parallel flow system includes a heat exchanger, such as an evaporator, having a plurality of parallel passages which are fluidly coupled between a plurality of channels in an inlet manifold assembly and a plurality of channels in an outlet manifold assembly. In operation, coolant (sometimes referred to as refrigerant) is distributed into and flows through the passages of the heat exchanger in a substantially perpendicular flow direction to that of the inlet and the outlet manifold assemblies. As an air flow passes through the heat exchanger, heat is exchanged between the air flow and the coolant fluid.
Non-uniform distribution of coolant in heat exchanger systems, particularly in parallel flow systems due to flow design, is well-known in the art. Non-uniform distribution of coolant may occur due to differences in flow impedances and pressure drops within and across the passages of the heat exchanger, non-uniform airflow distribution over external heat transfer surfaces, improper heat exchanger orientation or poor manifold and distribution system design. For example, in parallel flow systems, non-uniform distribution is caused in part by the varying lengths of internal coolant distribution paths within the inlet and the outlet manifold assemblies which may lead to varying pressure drops across the passages.
In the prior art, the channels in the manifold assembly have been tuned to reduce the adverse effects of non-uniform coolant distribution. For example, in those instances where airflow distribution through the heat exchanger is non-uniform, the flow profile in each channel may be tuned such that more coolant flows through passages in the heat exchanger that are exposed to higher percentages of the airflow. However, manufacturing problems may arise where the manifold assembly includes channels having differently tuned flow profiles. For example, a first channel having a first flow profile may appear externally similar to a second channel having a second flow profile different than the first flow profile. This external similarity may lead to the improper placement of the different channels in the manifold assembly resulting in improper coolant flow characteristics.